1. Field of Invention
The invention relates to a method of frame rate conversions and, in particular, to a method that utilizes a three-dimensional image interpolation algorithm to achieve the frame rate conversions.
2. Related Art
With the advance in technology, the quality of audio/video (AV) playing devices has also greatly improved. From the early video tapes to recent VCD's DVD's, storage media become more compact in size but larger in capacity. They provide users or consumers with more convenient storage media for carriage and better AV playing quality. However, one cannot neglect the operation efficiency of the data processing unit inside the AV playing devices. The large AV data have to be accompanied with an AV player with a powerful data processing unit, a high-resolution display and continuous frame playing.
Generally speaking, there often have problems about specification differences between AV data extraction and frame display. The specification differences include resolution and frame rates. Currently, frame pixel values are mostly adjusted using two-dimensional image interpolation methods. The method also duplicates frames close in the time axis, as shown in FIG. 1. In the drawing, F1 and F2 are frames that exist in the AV playing contents. F1′ is the frame formed by interpolating pixels along the time axis. The interpolation is done between F1 and F2. If the frame interpolation position determined by considering the frame rate playing speed is closer to F1, the interpolated frame F1′ is obtained by copying the corresponding pixels in F1. The rest frames are also formed in this manner. Although this method is more economical in operations and does not cause burdens for the system, it nevertheless cannot fully utilize the powerful operating unit of the AV player. Therefore, it is a kind of hardware waste.